1. Field
The present invention relates to a fuel cell system, and more particularly, to a fuel reforming or converting system capable of enhancing the efficiency of fuel cell system.
2. Description of the Related Technology
The fuel cell system has been researched and developed as an alternative to secure a power source corresponding to an increased demand of power and to solve environmental problems. In general, a fuel cell system generates electric energy through an electrochemical reaction; for example, between H2 and O2. Usually, hydrogen gas is obtained from a hydrogen-containing fuel. The hydrogen-containing fuel includes an alcoholic fuel such as methanol, ethanol, etc.; a hydro-carbonaceous fuel such as methane, propane, butane, etc.; and a natural gas fuel such as liquefied natural gas, etc.
Based on fuel, catalyst, electrolyte and the like, the fuel cell system is classified into a phosphoric acid fuel cell (PAFC), a molten carbon fuel cell (MCFC), a solid oxide fuel cell (SOFC), a polymer electrolyte membrane fuel cell (PEMFC), an alkaline fuel cell (AFC), etc. However, these different types of fuel cells operate generally by the same principle. Further, the fuel cell system can be used in various fields including a mobile device, transportation, a distributed power source, etc.
The PEMFC uses hydrogen obtained by reforming or converting the fuel containing hydrogen atoms in order to generate electricity. Usually the PEMFC system has good output capability, operates at a low temperature, starts quickly, and has a short response time. Further, the PEMFC system has very wide applications and can be used in the mobile device such as a car; the distributed power source for a house or a public building; a small power source for a portable electronic device; and the like. A typical PEMFC system includes a fuel container storing fuel, a reformer or converter reforming or converting the fuel to hydrogen gas and a fuel cell stack generating electricity using the hydrogen gas.